Speaking on the Tianxin stone in the Temple of Heaven in Beijing will feel particularly loud. This is because?

Because! The center of the table is slightly higher! Tilt down all around! When taichung people shout! Some sounds transmitted around are reflected by the surrounding stone railings! It hit a slightly tilted table and then reflected to the center of the table! So the echo is mixed with the original sound! Can't tell! I just think it's very loud!